Octagon shaped stackable flexible intermediate bulk container and method of manufacture

Abstract

A bulk bag comprises eight substantially identical side wall portions each containing a stiffening panel. A bottom wall is connected to the bottom edges of the side wall portions and may be provided with a discharge port. Alternatively, a discharge port may be provided in one of the side wall portions. The bulk bag may be provided with a top wall which may be either openable or secured in place. A pallet and/or lift loops may be provided for transporting the bulk bag and the contents thereof.

What is claimed is:  
     
       1. An octagon shaped bulk bag comprising: 
       eight double layer side wall portions disposed in an octagonal array and each comprising a stiffening panel receiving pocket;  
       eight stiffening panels each received in the stiffening panel receiving pocket comprising one of the side wall portions;  
       means for retaining the stiffening panels in the stiffening panel receiving pockets;  
       a bottom wall extending between and connected to the bottom of each of the side wall portions;  
       the bulk bag further comprising four side wall assemblies each comprising an inner fabric layer, an outer fabric layer, and spaced apart, vertically extending seams defining one of the side wall portions and two half side wall portions each extending outwardly from one of the vertically extending seams, the four side wall assemblies being sewn together end to end thereby connecting the half side wall portions to define the remaining four side wall portions.  
     
     
       2. The bulk bag according to claim  1  further characterized by a bottom seam extending along the bottoms of each of the four side wall assemblies for closing the lower ends of the stiffening panel receiving pockets thereof and for joining the bottom wall to the side wall assemblies; and 
       a top seam extending along the tops of all four side wall assemblies for closing the tops of the stiffening panel receiving pockets thereof.  
     
     
       3. A method of manufacturing octagon shaped bulk bags including the steps of: 
       providing eight substantially identical fabric sheets each having upper, lower, and side edges;  
       arranging the eight fabric sheets in four pairs each comprising an inner layer and an outer layer with the upper, lower, and side edges of each pair respectively aligned;  
       joining the inner and outer layers comprising each pair by seams extending parallel to the side edges and spaced apart to define a side wall assembly comprising a stiffening panel receiving pocket extending between the parallel seams and two half stiffening panel receiving pockets each extending outwardly from one of the parallel seams;  
       joining the inner and outer layers comprising the four pairs side edge to side edge to form four additional stiffening panel receiving pockets each comprising two half stiffening panel receiving pockets joined edge to edge;  
       providing an octagon shaped bottom wall;  
       securing the bottom wall to the lower edges of the inner and outer layers comprising each side wall portion;  
       providing eight substantially identical stiffening panels; and  
       positioning a stiffening panel in each of the stiffening panel receiving pockets.  
     
     
       4. The method according to claim  3  wherein the steps of providing eight identical fabric sheets is carried out by providing eight identical fabric sheets formed from woven polypropylene fabric. 
     
     
       5. The method according to claim  3  wherein the step of providing a bottom wall is carried out by providing a bottom wall formed from woven polypropylene fabric and wherein the step of securing the bottom wall to the lower edges of the inner and outer layers comprising the side wall portions is carried out by forming a seam which connects the bottom wall to the lower edges of the inner and outer layers comprised in the side wall portions. 
     
     
       6. The method according to claim  3  wherein the step of providing eight identical stiffening panels is carried out by providing stiffening panels formed from corrugated plastic material. 
     
     
       7. The method according to claim  3  including the additional step of at least releaseably securing the upper edges of the inner and outer panels comprising the side wall portions one to another and thereby securing the stiffening panels in the stiffening panel receiving pockets.